Two-shells-are-fired-from-a-canon-with-speed-u-each-at-angles-of-and-respectively-with-the-horizontal-The-time-interval-between-the-shots-is-t-They-collide-in-mid-air-after-time-T-from-the-firs

Question Number 20915 by Tinkutara last updated on 07/Sep/17

Two shells are fired from a canon with speed u each, at

angles of α and β respectively with the horizontal . The

time interval between the shots is t . They collide in mid

air after time T from the first shot . Which of the

following conditions must be satisfied ?

(a) α > β

(b) T \cos α = (T - t) \cos β

(c) (T - t) \cos α = T \cos β

(d) u \sin α T - \frac{1}{2} g T^{2} = u \sin β (T - t) - \frac{1}{2} g {(T - t)}^{2}

Answered by ajfour last updated on 08/Sep/17

A t t i m e T x_{α} = x_{β}

(u \cos β) (T - t) = (u \cos α) T

\Rightarrow T \cos α = (T - t) \cos β

h e n c e (a) n e e d b e s a t i s f i e d

a l s o a t t i m e T, y_{α} = y_{β}

h e n c e (d) s h o u l d a l s o b e

s a t i s f i e d .

Commented by Tinkutara last updated on 08/Sep/17

Thank you very much Sir!